Electromechanical actuating device



June 4, 1963 B. J. BARR ELECTROMECHANICAL ACTUATING DEVICE Filed April 15, 1961 FIG.

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Bernard J. Barr, INVENTOR. X ZW BY 4%9 United States Patent 3,092,208 ELECTROMECHANICAL ACTUATING DEVICE Bernard J. Barr, RED. 2, Mendota, Ill.

Filed Apr. 13, 1961, Ser. No. 102,904 1 Claim. (Cl. 185-40) (Granted under Title 35, US. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of royalty thereon.

This invention relates to a battery operated drive mechanism for actuating electromechanically operated devices such as clocks, recording instruments, and other constant speed devices.

It has been a practice to use electromechanical means to wind clock mechanisms and further to supply these means directly from a power source having a large current capacity.

Therefore, it is an object of this invention to use a low current capacity battery for winding of constant speed devices.

It is a further object of this invention to provide means for extending the life of the battery used for periodically actuating electromechanical devices.

It is still a further object of this invention to eliminate the need for delicate electromechanical devices for operating constant speed devices.

In one broad form of the invention, the apparatus comprises a mechanism for driving a clock continuously which utilizes a DC. voltage source and a time constant circuit. The time constant circuit includes an element which stores electrical energy delivered from the battery and delivers this energy at a particular instant of time to a means for driving the main spring of the clock. The time constant circuit allows for a slow continuous flow of current from the battery to the storage element.

One specific embodiment of the invention comprises a clock designed for continuous operation having an electromagnet for periodically actuating the main spring of the clock and a circuit consisting of a battery, a resistor and a capacitor for controlling the operation of the electromagnet. The battery charges the capacitor through the resistor during the time required for the clock to approach a nearly unwound condition. When the clock reaches a nearly unwound condition, a set of contacts closes and efiects the discharge of the capacitor. The capacitor discharges through a solenoid which actuates means to effeet the opening of the contacts and also winds the main spring of the clock. For optimum operation, the values of the resistor and capacitor are so determined to allow a near constant continuous flow of current from the battery.

The invention will be more fully understood through the following specification, taken in conjunction with the accompanying drawings, wherein like characters of reference denote corresponding parts in both views of which:

FIGURE 1 shows a diagrammatic embodiment of the invention as used with a simple pivoting electromechanical device.

FIGURE 2 shows a diagrammatic embodiment of the invention using a simple sliding electromechanical device.

Referring to FIGURE 1, there is shown a spring wound clock having a main spring 8 for supplying a driving force to the clock mechanism. The main spring 8 is connected to one end of a shaft 12 which upon counterclockwise rotation winds the clock, and which upon clockwise rotation, unwinds the clock. The other end of shaft 12 is secured to a T-shaped arm 14 disposed for limited angular movement about pivot point 16. Movement of arm 14 may be due to the unwinding of spring 8 (trans- "ice mitted through shaft 12) or due to the electromagnetic action of solenoid 18 as will be explained hereinafter. A contact 20 is located at one end of the arm 14 as shown in FIGURE 1, and is disposed so as to make or break contact with another contact 22. Contact 22 is attached to a stationary member (not shown) which may house the electrical components of this device. Contact 22 is electrically connected to one side of capacitor 24 and to one side of resistor 26. The other side of resistor 26 is connected through a DC. voltage source 28 to the other side of capacitor 24 and to one side of the solenoid 18. The other side of the solenoid 18 is connected to contact 20.

The circuit operates in the following manner: The clock 10 in a wound condition holds contact 20 away from contact 22 by means of shaft 12 and arm 14. The DC. voltage source 28 charges capacitor 24 through resistor 26 to a value slightly less than that of the source 28 and does so in a time dependent on the values of resistor 26 and capacitor 24. The time of charge is regulated to correspond with the time required for clock 10 to unwind and move contact 20 to a position of connection with contact 22. When contact 20 connects with contact 22, capacitor 24 discharges through solenoid 18 which rotates arm 14 in a direction to wind clock 10. This cycle is repeated so as to keep clock 10 Wound to such a degree that it will continue to operate at its constant speed. In FIGURE 1, clock 10 might well be any constant speed device such as a tape recorder, recording instrument, etc.

In FIGURE 2, instead of using a pivoted arm and a spring wound clock, a slideable arm 36 and a weight driven clock 34 are provided. In this embodiment, the weight driven clock 34 operates on a ratchet principle whereby the weight driven chain 32 rotates two gears engaged by a pawl (not shown) to turn the indicator and the clock mechanism in a clockwise manner. Upon contact of members 22 and 30 the gears have independent movement so that the chain is allowed to rotate in a counterclockwise manner which the indicator remains stationary. Weight 38 acting through chain 32 drives the mechanism of clock 34. Arm 36 is connected to chain 32 so as to periodically raise weight 38 through actuation of solenoid 18 and provide means for operation of clock 34. A contact 30, similar to contact 20 of the device shown in FIGURE 1, is attached to arm 36 and disposed for making and breaking contact with contact 22. The elements 18, 22, 24, 26 and 28 function in the same manner as disclosed in the operation of the device of FIGURE 1 to provide for the operation of this particular type of constant speed device.

Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claim, the invention may be practiced otherwise than as specifically described.

What is claimed is:

An electromechanical actuating device comprising a cylindrical mechanism having constant speed movement, a spirally wound spring connected to one end of said mechanism, a rotatable shaft coaxially aligned with said mechanism and having one end attached to said spring, the other end of said shaft attached to a T-shaped arm, said arm disposed perpendicular to said shaft and adapted for limited angular movement thereabout, a solenoid operatively associated with one side of said arm, the other side of said arm having a first electrical contact attached thereto, said contact electrically connected through said solenoid to one end of a DC. voltage source and one end of a capacitor, a second electrical contact adjacent said first contact and stationary with respect to said first a first position responsive to the unwinding of said spring whereby said contacts are in contact with each other. and to a second position responsive to the actuation of said solenoid whereby said contacts are separated from each other, said solenoid being actuated by the discharge of said capacitor.

References Cited in the file of this patent UNITED STATES PATENTS Blumberg et a1. Oct. 9, 1917 Fils Sept. 17,1929 7 Quartier May 6, 1930 Korfhage Mar. 20, 1934 

